Electrical heater.



F. E. CARLSON.

' ELECTRICAL HEATER.

APPLICATION FILED DEC. 28, 1014.

Patented Nov. 7, 1916.

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UNITED STATES PATENT OFFICE.

FREDERICK 'E. CABLE-3011', 01 NEW BRITAIN, CONNECTICUT, ASSIGNOR TO LANDERS,

FBABY & CLARK, F NEiV BRITAIN,

NECTICUT.

CONNECTXCUT, A CORPORATION OF CON ELECTRICAL HEATER.

Application filed December 28, 191 1.

To all whom it may concern Be it known that l, FREDERICK E. CARL- SON, a citizen of the United States, and a resident of New Britain, in the county of Hartford, State of Connecticut, have invented certain new and useful Improvements in Electrical Heaters, of which the following is a specification.

This invention relates to electrical heaters, and more particularly is intended for use as an immersion heater, where the body of the heater is dropped into a pan, cup, or glass of water to raise its temperature. Certain features of the invention may be susceptible of broader application. However the immersion heater is the embodiment of the invention which has been selected for illustation and description.

In the drawingslligure l is a side view of a heater made in accordance witlrmy invention. Fig. 2 is a sectional View thereof. Fig. 3 is another sectional view at right angles to the section of Fig. 2, but showing the inner shell and coil in full. Fig. 4 is a bottom view of the complete heater shown in Fig. 1. Fig. 5 is a transverse sectional view on the line of Fig. 3, but with the outer shell removed.

Referring to the drawings, a. is the interior shell of cup shape to provide a chamher I), and flanged at its lower end as at c to contact with the wall of the outer shell d, which has secured in its upper end a stem, 6, the end of the stem carrying a ring f, to which some suitable electrical connection, indicated generally at g, may be secured. The two shells, 0, cl, are connected by the tubular member h which provides a vent for the chamber 7). The contacting surfaces atthe points indicated at v, w, as, 7 z, are preferably brazed together to form a securely built-up unitary structure.

Surrounding the interior shell (I, are strips of insulating material '2, about which the heating coil is wound and by which it is kept out of contact with the inte *ior shell. The terminals of the beating coil are brought up to insulated conducting strips 4,

4, which extend up through the stem c, where they may be attached to the electrical connection g, these conducting strips being bound together by insulated clamps 5.

After the parts have been assembled to gether, a very fine granular electrical insulating material is poured in at the top of Specification of Letters Patent.

Patented Nov. '7, 19.16.

Serial No. 879,265.

the stem and caused to flow down and completely fill in the space between the inner and outer shells a, (Z, packing in around the heater coil, and in fact completely filling the interior of the structure up to near the top of the stem 6. A plugof fibrous material, such as asbestos wool, is then packed into the top of the stem 0 and preferably dipped in parafiin or some other waterproofing material. The granular materia which has been used with success has been in the form of a very fine sea sand, though of course any proper material could be used.

The outer shell (l extends below the inner shell 1:. and is apcrtured to receive the ends of a spring guard ring 10 which acts as a support for the heater, and if it be taken from the water and laid on its side on a table, holds the heated portion of the structure away from the table. and thus avoids burning. It can be readily disengaged from the h ater if it is not desired to use it.

The construction herein described presents a large heating surface within a small coinpass, by virtue of the chamber (1. The manufacture and assembly of the device under this method of construction are extremely simple and inexpensive. The complete assembly of all the parts, and the subsequent packing with the very finc granular material to completely till the stem and the space between the shells. a li'ord an extremely etiicient support for the heating coils, provide a large body of heat radiating material. and a permanent and effective electrical insulator, insuring against short circuiting by reason of the shifting of position of any of the coils.

It is not desired to give the impression that the invention is limited to the embodiment illustrated, since it is evident that it is susceptible of various modifications and alterations.

I claim as my invention 1. in a device of the character described, spaced shells, an electrical heater located between the shells, insulating means for holding it out of contact with said shells and a connninuted packing filling the space between said shells and entirely surrounding and embeddin said heater.

2. In a device or the character described, spaced shells, an electrical heater located between the shells, insulatingmeans for holding it out of contact with said shells and a comminuted packing of insulating material filling the space between said shells and entirely surrounding and embedding said heater.

3. In a 'device of the character described, spaced shells, an electrical heater located between the shells, insulating means for holding it out of contact with said shells-and a packing of finely divided granular material filling the space between said shells and entirely surrounding and embedding said heater.

4. In a device of the character described, a pair of spaced cupped shells nested to.- gether and secured together at their edges, the outer shell having an opening in its top, a tubular stem with an end secured in said opening to said outer shell, an electrical heater located in the space between said shells, means for holding it out of contact with said shells, and a comminuted packing of insulating material filling the space between said shells and entirely surrounding and embedding said heater. 1

5. In a device of the characterdescribed, a pair of cup-shaped shells nested together and with their walls spaced, apart and their lower edges secured together, a comm-inuted packing of insulating material filling the space between the shells, an electrical heater embedded in said packing, and a tubular sleeve connected between the walls of said shells. r

6. In a device of the character described, a pair of cup-shaped shells nested together and with their walls spaced apart and their lower edges secured together, a comminuted packing of insulating material filling the space between the shells, an electrical heater embedded in said packing, and a passage extending from one shell to the other through said packing.

7, In a device of the character described, a pair of cupped, spaced shells nested together and with their edges secured together, a stem secured to the end of the outer shell, a connection plug secured at the end of said stem, an electrical heater mounted in the space between said shells and with its terminals passing through said stem to said connection plug, and a packing of finely divided granular material filling said stem and the space between said shells, and embedding said heater.

8. In an electrical heater of the immersion type, a metallic body, an electrical heater located within said body, means for insulating said heater from said body, and a guard detachably secured to said body and iirojecting beyond the outer wall thereof.

9. In an electrical heater of the immersion type, a metallic body, an electrical heater located within said body, means for insulating said heater from said body,. and a wire guard of greater size than said body I detachably secured thereto. $5

10. In a device of the character described,

a cupped inner shell, a cupped outer shell with an, opening in its top, said shells being nested together in spaced relation with their edges united, a tubular stem with an end secured in the opening in the top of said outer shell, an electrical heater located in the space between said shells, means for holding it out of contact therewith, and a comminuted insulating material fillingthe space between said shells and said tubular stem and surrounding said heater.

FREDERICK s. canteen.

Witnesses:

*BRAINERD W. Brown,

HOWARD C. HUMASON. 

